They comprise for example:
at least one pole with separable contacts,
a magnetic trip and/or a thermal trip associated with pole for controlling the opening of the contacts via a tripping mechanism,
at least one manual control button disposed on a front face of the case and acting on the tripping mechanism for opening and closing the contacts,
an electromagnet causing opening and closing of the contacts in response to the energization and to the deenergization of its coil, via a mobile assembly coupled to its armature, whereas a return system urges the armature towards a return position.
When the coil of the electromagnet is supplied with power, a holding current remains applied to this coil and the contacts of the apparatus remain in a stable closed or open state unless an excess current fault has been detected by the tripping devices-until the supply to the coil is interrupted. The breaker apparatus thus operates in "contactor" mode.
It would be desirable to use the same apparatus for providing a "remote controlled breaker" mode control, i.e. with the coil at present fed with current pulses, the contacts of the apparatus should close and open alternately at each pulse, while remaining maintained in their position until the next pulse.